“The third quarter of 2011 saw a continuation of the year’s strength in U.S. retail e-commerce spending, even in the face of renewed economic headwinds and uncertainty facing the U.S. consumer,” said comScore chairman Gian Fulgoni. “As we approach the critical holiday shopping season, we are optimistic about the continued health of the e-commerce sector despite other factors – including stubbornly high unemployment and volatile financial markets – currently weighing on the economy. More consumers than ever before are relying on the online channel for product and pricing information, which along with the Internet’s fundamental appeal of convenience and attractive pricing, are contributing to the sustained upward momentum in e-commerce spending.”

The 13-percent growth in the quarter was primarily a function of an increase in the number of buyers (up 22 percent), with 74 percent of all Internet users making at least one online purchase in the quarter.

40 percent of e-commerce transactions included free shipping, down from a peak of 49 percent in Q4 2010. Free shipping rates tend to peak during the holiday season.

Webinar Series: State of the U.S. Online Retail Economy through Q3 2011

Join Gian Fulgoni and Andrew Lipsman, VP of Industry Analysis, as they present an update of the state of the U.S. online retail economy through Q3 2011 in a live webinar on Tuesday, November 15 from 2-3 p.m. EST / 1-2 p.m. CST / 11-12 p.m. PST.

This installment includes an overview of e-commerce trends in the third quarter of 2011, including an analysis of the impact of mobile on bricks-and-mortar retail.

About comScorecomScore, Inc. (NASDAQ: SCOR) is a global leader in measuring the digital world and preferred source of digital business analytics. For more information, please visit www.comscore.com/companyinfo.